IMHO... A firearm to be used in close, has to be able to be swung about it's role of house, or back yard shoot out makes that a given.
A shotgun is big and clumsy, can be grabbed by the in house criminal, much easier than a hi-cap pistol. Not sure on my home being ever attacked by a group, admittedly anything could happen. My Steyr AUG with a 16" Barrel, having a total length of 28" is real handy once the range starts to open up.
My Son had a contract of some 6 months duration, a large Jewelry Store.
Indoors with 9mm pistol, Glock 19 my favorite pistol. The major reason we were employed, the hang around group from the local hood. Sitting on vehicles, foul language, not appreciated by the Ladies at quitting time.
The first evening of this older bearded uniformed gent, with 12 gage pump, in both hands! Fixed that problem.
An 18" Mossberg Pump with SECURITY in 1" white letters on the black polymer butt-stock, was not too heavy for the 5 minutes I carried it!
I heard it well articulated by a local teen "The old dude got's a gage" he was correct, on both counts, after all.